A magnetic recording medium is wound at a high speed and therefore there are problems that a surface of the support opposite to a magnetic recording layer is readily electrostatically charged and also worn out. Due to the above problems, improvement in the durability of magnetic recording media is highly desired.
Hitherto, the improvement in durability of magnetic recording media has been achieved by providing a backing layer and carbon black is incorporated into the backing layer to prevent static charging and calcium carbonate is added to the backing layer to adjust unevenness of the surface thereof, as disclosed in Japanese Patent Publication No. 8321/74.
However, in the above conventional method, calcium carbonate does not have sufficient affinity with respect to binders and therefore, it can be easily scraped away from the backing layer, causing drop out. Thus satisfactory durability cannot be obtained.